In this Jan. 29, 2011, file photo, then-Joint Chiefs Vice Chairman Gen. James E. Cartwright takes part in a media briefing at the Pentagon in Washington.

ASSOCIATED PRESS

Retired Gen. James Cartwright, the former vice chairman of the U.S. Joint Chiefs of Staff, is the target of a Justice Department investigation into the leak of classified information included in a book by New York Times correspondent David Sanger, a source told ABC News.

Published in mid-2012, Sanger's book, "Confront and Conceal," and a New York Times article adapted from the book, included revelations about the Stuxnet computer virus that was part of a covert U.S.-Israeli cyberattack to sabotage Iran's nuclear enrichment program.

Cartwright, 63, served as the vice chairman of the Joint Chiefs of Staff from 2007 to 2011. Prior to that, the four-star Marine general had been in command of U.S. Strategic Command. He is also a defense consultant for ABC News.

A source familiar with the case confirmed that Cartwright is the target of a year-long Justice Department investigation into the leaks of classified information included in Sanger's book and article.

"He is the target of the investigation," the source said.

The Stuxnet virus was part of a highly classified covert program known as "Olympic Games" that used computer code to successfully target Iranian nuclear enrichment facilities to delay that country's efforts to potentially develop a nuclear weapon.

The revelations sparked outrage among lawmakers and triggered a Justice Department probe into who had been behind the leaks included in the book.

NBC News was first to report that Cartwright was the focus of a criminal probe of the leaks. The source could not confirm the NBC report that Cartwright is specifically being targeted for a leak of information about the Stuxnet computer virus that was first revealed in Sanger's book.

ABC News confirmed that prominent Washington attorney Greg Craig is representing Cartwright in regard to a Justice Department matter, but he declined to comment on the report that Cartwright is the subject of the leaks probe.

Cartwright retired from the Marine Corps in August 2011. He now serves as the Harold Brown Chair in Defense Policy Studies at the Center for Strategic and International Studies, a Washington think-tank.

Government officials referred questions to the U.S. Attorney's Office in Maryland, which has been conducting the leak investigation of Sanger's book. That office declined to comment.